Familial thrombocytopaenia in three male siblings

Abstract

INTRODUCTION & OBJECTIVES: Familial thrombocytopaenia is uncommon. Specific molecular defects have been identified in some families. We describe three male siblings with thrombocytopaenia and other immune related findings. The parents are healthy and non-related. METHODS: Clinical and investigative findings were obtained from the brothers and their parents. RESULTS: Case 1: A 15 year old male presented with spontaneous ecchymotic patches and oral mucosal bleeding. Platelet count was 1000/mm3, mild hepatomegaly was present on ultrasonography and IgA was raised. As the response to IV methyl-prednisolone was poor, IVIG, prednisolone and azathioprine were used. He has had recurrent RT infections and as his latest platelet counts are suboptimal, Rituximab is being considered. Case 2: A 19 year old male was found to have thrombocytopaenia whilst being investigated for a large scalp haematoma aged 2 years. He had been treated with oral prednisolone and needed pulse IV dexamethasone. Presently he is off steroids and the platelet count is 54000/mm3. Serum IgM is reduced and IgA is raised. He has chronic bilateral lower limb eczema, an atrio-fascicular accessory pathway and gets recurrent RT infections. Case 3: A 12 year old male had fever, cervical lymphadenopathy and hepatosplenomegaly aged 3 years. He then developed AIHA and thrombocytopaenia. The thrombocytopaenia persisted and was treated with prednisolone and cyclosporine. Aged 9 years, he developed SLE and a year later, class IV lupus nephritis was found on renal biopsy. CONCLUSION: An AR or XR genetic cause is likely in this family. The identification of the exact molecular defect may help with selecting appropriate medications to target abnormal immune pathways.